#!/bin/sh

CONFDIR=@certsdir@
DAYS=2190
KEY_SIZE=2048
export KEY_SIZE=${KEY_SIZE}

TMPFILE="/tmp/fs-ca-$$-$(date +%Y%m%d%H%M%S)"

COMMON_NAME="FreeSWITCH CA"
ALT_NAME="DNS:test.freeswitch.org"
ORG_NAME="FreeSWITCH"
OUTFILE="agent.pem"

umask 037

check_ca() {
	for x in cacert.pem cakey.pem config.tpl; do
		if [ ! -e "${CONFDIR}/CA/${x}" ]; then
			return 1
		fi
	done

	return 0
}

setup_ca() {
	if check_ca; then
		echo "Existing CA found in \"${CONFDIR}/CA\""
		echo "(Use \"gentls_cert remove\" to delete)"
		exit 1
	fi

	echo "Creating new CA..."

	if [ ! -d "${CONFDIR}/CA" ]; then
		mkdir -p -m 750 "${CONFDIR}/CA" || exit  1
	fi

	if [ -e "${CONFDIR}/CA/config.tpl" ]; then
		if [ $0 -nt "${CONFDIR}/CA/config.tpl" ]; then
			echo "WARNING! genttls_cert has a modified time more recent than ${CONFDIR}/CA/config.tpl remove config.tpl to re-generate it"
		fi
	else
		cat > "${CONFDIR}/CA/config.tpl" <<-EOF
			[ req ]
			default_bits            = \$ENV::KEY_SIZE
			prompt                  = no
			distinguished_name      = req_dn
			x509_extensions         = v3_ca

			[ req_dn ]
			commonName              = %CN%
			organizationName	= %ORG%

			[ server ]
			nsComment="FS Server Cert"
			basicConstraints=CA:FALSE
			subjectKeyIdentifier=hash
			authorityKeyIdentifier=keyid,issuer:always
			subjectAltName=%ALTNAME%
			nsCertType=server
			extendedKeyUsage=serverAuth

			[ client ]
			nsComment="FS Client Cert"
			basicConstraints=CA:FALSE
			subjectKeyIdentifier=hash
			authorityKeyIdentifier=keyid,issuer:always
			subjectAltName=%ALTNAME%
			nsCertType=client
			extendedKeyUsage=clientAuth

			[ v3_ca ]
			subjectKeyIdentifier=hash
			authorityKeyIdentifier=keyid:always,issuer
			basicConstraints=CA:TRUE

		EOF
	fi

	sed \
		-e "s|%CN%|$COMMON_NAME|" \
		-e "s|%ORG%|$ORG_NAME|" \
		-e "/%ALTNAME%/d" \
		-e "s|CA:FALSE|CA:TRUE|" \
		"${CONFDIR}/CA/config.tpl" \
			> "${TMPFILE}.cfg" || exit 1

	openssl req -out "${CONFDIR}/CA/cacert.pem" \
		-new -x509 -keyout "${CONFDIR}/CA/cakey.pem" \
		-config "${TMPFILE}.cfg" -nodes -days ${DAYS} -sha256 >/dev/null || exit 1
	cat "${CONFDIR}/CA/cacert.pem" > "${CONFDIR}/cafile.pem"
	cp $TMPFILE.cfg /tmp/ssl.cfg
	rm "${TMPFILE}.cfg"

	echo "DONE"
}

generate_cert() {
	local val=""

	if ! check_ca; then
		echo "No existing CA found, please create one with \"gentls_cert setup\" first"
		exit 1
	fi

	echo "Generating new certificate..."

	echo
	echo "--------------------------------------------------------"
	echo "CN: \"${COMMON_NAME}\""
	echo "ORG_NAME: \"${ORG_NAME}\""
	echo "ALT_NAME: \"${ALT_NAME}\""
	echo
	echo "Certificate filename \"${OUTFILE}\""
	echo
	echo "[Is this OK? (y/N)]"
	read val
	if [ "${val}" != "y" ] && [ "${val}" != "Y" ]; then
		echo "Aborted"
		return 2
	fi

	sed \
		-e "s|%CN%|$COMMON_NAME|" \
		-e "s|%ALTNAME%|$ALT_NAME|" \
		-e "s|%ORG%|$ORG_NAME|" \
		"${CONFDIR}/CA/config.tpl" \
			> "${TMPFILE}.cfg" || exit 1

	openssl req -new -out "${TMPFILE}.req" \
		-newkey rsa:${KEY_SIZE} -keyout "${TMPFILE}.key" \
		-config "${TMPFILE}.cfg" -nodes -sha256 >/dev/null || exit 1

	openssl x509 -req -CAkey "${CONFDIR}/CA/cakey.pem" -CA "${CONFDIR}/CA/cacert.pem" -CAcreateserial \
		-in "${TMPFILE}.req" -out "${TMPFILE}.crt" -extfile "${TMPFILE}.cfg" \
		-extensions "${EXTENSIONS}" -days ${DAYS} -sha256 >/dev/null || exit 1

	cat "${TMPFILE}.crt" "${TMPFILE}.key" > "${CONFDIR}/${OUTFILE}"

	rm "${TMPFILE}.cfg" "${TMPFILE}.crt" "${TMPFILE}.key" "${TMPFILE}.req"

	echo "DONE"
}

remove_ca() {
	echo "Removing CA"

	if [ -d "${CONFDIR}/CA" ]; then
		rm "${CONFDIR}/CA/"*
		rmdir "${CONFDIR}/CA"
	fi

	echo "DONE"
}
OUTFILESET="0"
command="$1"
shift

while [ $# -gt 0 ]; do
	case $1 in
		-cn)
			shift
			COMMON_NAME="$1"
			;;
		-alt)
			shift
			ALT_NAME="$1"
			;;
		-org)
			shift
			ORG_NAME="$1"
			;;
		-out)
			shift
			OUTFILE="$1"
			OUTFILESET="1"
			;;
		-days)
			shift
			DAYS="$1"
			;;
	esac
	shift
done


case ${command} in
	setup)
		setup_ca
		;;

	create)
		EXTENSIONS="server"
		generate_cert
		;;
	create_server)
		EXTENSIONS="server"
		generate_cert
		;;
	create_client)
		EXTENSIONS="client"
		if [ "${OUTFILESET}" = "0" ]; then
			OUTFILE="client.pem"
 		fi
		generate_cert
		;;

	remove)
		echo "Are you sure you want to delete the CA? [YES to delete]"
		read val
		if [ "${val}" = "YES" ]; then
			remove_ca
		else
			echo "Not deleting CA"
		fi
		;;

	*)
		cat <<-EOF
		$0 <setup|create_server|create_client|clean> [options]

		  * commands:

		    setup  - Setup new CA
		    remove - Remove CA

		    create_server - Create new certificate (overwriting existing!)
		    create_client - Create a new client certificate (overwrites existing!)

		  * options:

		   -cn       Set common name
		   -alt      Set alternative name (use prefix 'DNS:' or 'URI:')
		   -org      Set organization name
		   -out      Filename for new certificate (create only)
		   -days     Certificate expires in X days (default: 365)

		EOF
		exit 1
		;;
esac